Checking for exhaust leak?
Road Captain
Joined: Jun 2011
Posts: 594
Likes: 10
From: Seminole County, FL
Try a laser infra red thermometer, you will see temperature spikes without burning your fingers or your bike. If you do it with a cold engine your leaks will be real easy to spot. It will work while hot too, but the hot spots won't be as obvious.
I like the cigar smoke approach, good excuse for a vintage 1992 Rocky Patel.
I like the cigar smoke approach, good excuse for a vintage 1992 Rocky Patel.
Road Captain
Joined: Jun 2008
Posts: 502
Likes: 3
From: Sarasota, Florida
The best way I found is to buy a long candle (10"-12") The length will keep you from burning nuckles. Move the flame around the exhaust port. If there's a leak the flame will go out. I never had much luck with the smoke method.
Road Warrior
Joined: Dec 2006
Posts: 1,321
Likes: 12
From: Shorewood IL
I will be trying some of these methods as well. I just put on a set of 2:1 pipes and am getting a pop on decel. I used new gaskets at the head and have retightened the header flange bolts a few times now. Still pops. I was thinking there were only two locations where my pipes have connections, at the head and the slip on. Now remember I have plugs down by the trans where the stock O2 sensors went. Now I have to check those....
Outstanding HDF Member
Joined: Feb 2007
Posts: 2,976
Likes: 49
From: Northern California
I stuffed the ends of the mufflers with rags nice and tight, on one side I stuck a long air blower tip from the compressor and stuffed the rags tight on that as well.
I used a smoke pen but anything that smokes or makes a candle like flame should work too.
It took 2 people to do it but made the leaks easy to find and not get burned in the process.
We could actually hear the leaks as well because the motor was not running. Huge leaks at the connection of the mufflers to pipes, used bike so who knows what happened here, I used muffler joint sealant and popping was gone.
I used a smoke pen but anything that smokes or makes a candle like flame should work too.
It took 2 people to do it but made the leaks easy to find and not get burned in the process.
We could actually hear the leaks as well because the motor was not running. Huge leaks at the connection of the mufflers to pipes, used bike so who knows what happened here, I used muffler joint sealant and popping was gone.
Banned
Joined: Jul 2008
Posts: 1,036
Likes: 67
what I have done is to take a paper towel and roll it to look like a long cigar, nice and tight...next light one end and let it burn for a bit and then blow it out so that there are still red hots but no flame...there will be lots of smoke..now hold the smoldering part near all the suspect joints and you will see the smoke blow away if there is a leak, and if it is bad you might even see the paper burst back into flames...keep some water near by just in case it gets out of hand...
Outstanding HDF Member
Joined: Feb 2007
Posts: 2,976
Likes: 49
From: Northern California
Take a fog machine, warm it up good and run it a cycle right in the mufflers. Stuff rags in one, stuff rags and a air hose in the other and look for the smoke.
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Cruiser
Joined: Apr 2012
Posts: 217
Likes: 39
From: Cleveland
Now that's an interesting take on how to do it. If only I had a fog machine!!!
Seasoned HDF Member
Joined: Dec 2004
Posts: 7,934
Likes: 43
From: Bloomfield, NM
Take a length of rubber hose, like a fuel line, hold it to your ear and run the other end around where you think the leak might be. If it is much of a leak you can hear and feel it.
Bill
Bill